Combustion chambers of gas turbine plants are conventionally equipped with one burner or with a plurality of burners. A burner of this type may be equipped, for example for pilot operation or for stabilizing a flame front in the combustion chamber, with an injection device for introducing gaseous and/or liquid fuel into the burner. An injection device of this type comprises a body which is arranged in the burner and which has at least one nozzle for introducing the fuel into the burner. The injection device is conventionally a lance as known for example from the DE4326802, the shaft of which forms the body arranged in the burner and usually equipped with a plurality of nozzles. In this case, a configuration is customary in which the nozzles introduce the fuel radially into the burner with respect to a longitudinal mid-axis of the shaft. In interaction with an oxidizer flow flowing axially through the burner, an axial fuel deflection is obtained, and also an intensive intermixing of the fuel flow with the oxidizer flow.
While conventional burners preferably operate with natural gas which is introduced via the lance, in modern gas turbine plants there is the desire to use fuels containing hydrogen gas. Fuels containing hydrogen and also carbon monoxide can be produced, for example, by means of a partial oxidation of long-chain hydrocarbons. A fuel gas of this type may also be designated as synthesis gas or syngas.
Conventional burners are unsuitable for use with such a fuel containing hydrogen gas. In comparison with natural gas, a fuel gas containing hydrogen gas possesses markedly higher reactivity, which leads to lower ignition temperatures, shorter ignition delay times and higher flame velocities. If a highly reactive fuel of this type is used in a burner designed for natural gas, the fuel ignites before sufficient intermixing while the oxidizer gas takes place. The pollutant emissions consequently increase. Moreover, the risk of flashbacks rises. In order to remedy this, for example, the inflow velocity at which the fuel gas is introduced into the burner could be increased. In conventional burners, however, this may lead to the fuel gas possessing an increased concentration in the region of a burner wall, which ultimately may likewise lead to increased pollutant values and even flashback, at the latest in the combustion chamber.
What is needed is a burner allowing an improved intermixing of fuel and oxidizer and therefore reduced pollutant emissions, even when it is operated with a fuel containing hydrogen gas.